It is generally recognized that success in games known as "billiards" (e.g., pocket billiards, American snooker, carom billiards) is dependent upon proper aiming and a knowledge of angles and deflections. It is particularly important that the player properly determine the precise point of aim for an accurate shot if, thereafter, he is to skillfully and successfully execute the shot. While the latter is a matter of practice and experience, no amount of practice or experience will provide an effective shot if the initial point of aim is incorrectly determined.
Contrary to popular belief, the correct point of aim is not necessarily an imaginary spot on the object ball. To illustrate, the novice or beginning player will frequently assume that the desired point at which the periphery of the cue ball should contact the object ball is also the correct point for aiming the center of the cue ball. However, the knowledgeable or "expert" player knows this assumption to be incorrect, and that the true point of aim for the center of the cue ball is spaced from the object ball (along the intended line of travel of the latter) a distance which is equal to one half the diameter of the cue ball. The knowledgeable player also knows that if the cue ball is shot so that its center passes over this "true" point of aim (without English) the object ball will move along the intended line of travel, viz., to a pocket or desired point for rebound on the periphery of the table. The problem of determining a correct point of aim is complicated by the fact that, whereas many players will routinely aim the center of the cue ball, others will effectively aim a particular peripheral portion of the cue ball at the desired point of contact, with substantially identical results. As a consequence, the principle of true point of aim is generally misunderstood, even by players who play at billiards with relative frequency, and is often poorly or incorrectly explained by many would be experts on the subject.
Some efforts have recently been made to correctly present the principle of true point of aim, and to provide devices which would teach such principle to the beginning or novice player. Particular devices for such purpose are disclosed, for example, in Miller Pat. No. 3,220,122, Murch Pat. No. 3,410,555, and McGowan Pat. No. 3,411,779. In general, such devices are cumbersome and unwieldy and undesirably complex in nature. The devices are, moreover, not truly suited for training purposes, and are soon discarded as impractical for the intended purpose.
A simple, inexpensive, easily used device for training and teaching the principle of true point of aim is therefore highly to be desired.